When did the current explosion of superhero movies start? Was it in 2000, when X-Men was released, and a critical consensus emerged that these movies could be pretty good? Was it 2002, when Spider-Man proved that they could be both beloved and juggernauts? It might have actually been 2008, when Nolan’s The Dark Knight and Marvel’s Iron Man (directed by Jon Favreau, although that’s easy to forget) both hit theaters.
Superhero movies are almost never sold on their stars

While pinpointing the start of this era of domination is difficult, all of these movies share something crucial — none of them starred the biggest actors on the planet. The cast of X-Men included a couple of theater veterans, as well as a young cast of actors who would go on to stardom but had not yet broken through in any major way.
Hugh Jackman was not Hugh Jackman in 2000. The same was true of Spider-Man , which cast two teen stars to play Peter Parker and Mary Jane in Spider-Man . These were actors that audiences could have seen before, but not ones that they were overly familiar with.
Even The Dark Knight and Iron Man were not using A-list actors in those roles. Robert Downey Jr. had been a major star, but crucially, Iron Man was a comeback for RDJ and one that was obviously enormously profitable for him and for Marvel, and Christian Bale was still a star on the rise.
All of these actors, then, became closely associated with the roles they were cast in, and some of them struggled to find a way to break out of the confines of these hugely iconic characters.
For the most part, the biggest stars in the world have avoided playing superheroes, and that’s with good reason. There was a time in cinema when movie stars were the primary reason audiences attended films, but that period has been replaced by the era of superhero movies.
You might love Chris Evans’ portrayal of Captain America, but you go to a Captain America movie to see the character, not the performer. That should be true of almost every superhero. You want to see the character and not the actor.
Of course, as Chris Evans continued to play Captain America, and the Marvel universe kept succeeding, Marvel ran into an inevitable problem. The nameless actor they’d cast in the part was suddenly a name, which meant that he no longer blended into the universe as seamlessly as he once had.
This is a good problem, but one that helps to explain why Marvel has had so much difficulty behaving exactly the way comic books themselves do. While at one point it made sense for Evans and RDJ to share billing somewhat regularly, the cost of that billing continued to grow as the movies themselves became more successful.
There’s only so much growth you can attain before your stars are at least as important to the movies as the characters themselves, which is why Marvel basically had to leave one generation of talent behind with Endgame and attempt to launch an entire separate one.
Superman gets this exactly right

James Gunn’s Superman movie, and frankly all of his superhero films, have understood that actors are not what sell these movies. That doesn’t mean they aren’t essential to the movie’s ultimate success. David Corenswet is not an actor most people know, but he’s basically a perfect Superman, and the same is true of Rachel Brosnahan’s Lois Lane. These are talented actors who aren’t necessarily movie stars, and that’s exactly why they work so well.
Nicholas Hoult is a bigger name than both of them, but even he is not as big an actor as Gene Hackman was in the original Superman movies or as Jack Nicholson was in 1989’s Batman . And, crucially, hiring bigger actors to play villains makes sense, because they don’t necessarily have to return for sequels the way your star inevitably does.
Of course, part of the reason that Gunn’s new DCU can get away with this is because it’s a nascent universe. If it lasts a decade the way Marvel’s universe ultimately did, then Corenswet will likely become more and more crucial to the success of these movies and become a star himself as a result. For now, Superman positioned the DCU to get off on the right foot.
Movie stars are brands in and of themselves

Timothée Chalamet would be a weird Spider-Man. He’s theoretically the right age, and he even comes from the kind of New York background that you would think might make him a perfect fit for the role. Nevertheless, were he to actually take on the part, it would feel strange, because Chalamet has made a career out of playing different, more serious roles.
Seeing him play someone less serious who was part of a much bigger universe and might have to be in eight of these movies would devalue the capital he has built up as a star worth seeing no matter what he’s in.
There’s a reason Brad Pitt and Leonardo DiCaprio have never signed on to a Marvel movie. They want to sell movies on themselves, and they know that Marvel is not selling movies on the actors in them. That’s not to say that there haven’t been genuinely great performances in Marvel movies of all kinds.
Movie stars are a dying breed, and we should be glad that they aren’t using their finite time and capital to make Marvel movies. Movie stars are supposed to exist so that, occasionally, people will go to see F1 or A Complete Unknown in addition to the new Fantastic Four movie.
Movies thrive when there’s a diversity of stuff that you can check out. That’s part of Marvel’s problem over the last five years: it has felt more and more like the only game in town. Casting great actors is part of the Marvel project, but they haven’t ever put movie stars at the center of their movies for a reason.